American Justin Thomas holds a two-stroke advantage at 14-under over Ian Poulter and Rory McIlroy, Day alone in fourth at 10-under.
The Firestone course proved a trickier proposition Saturday after two days of soft conditions and low scoring, Rickie Fowler’s 5-under 65 the best of the day.
Marc Leishman is a shot behind Day and sharing fifth alongside Kyle Stanley, the Victorian’s 67 bettered by only four players on day three.
Wade Ormsby is next best of the Australians at 2-under and T34, Cameron Smith 1-under and T36 while Adam Scott fought back from a 5-over 75 Friday with a 3-under 67 to get back to even par and T43.
It is Day, though, who has the best chance of securing a 13thPGA Tour title though says he will need to find more fairways if he is to do it.
“I need to drive it a little bit better, as you can see,” he told CBS’ Amanda Balionis after the round when shown a graphic of his driving statistics showing he hit only four fairways.
.@JDayGolf trying to keep pace with the leader.August 4, 2018
“Just not quite happy with the driver. I’m actually hitting the 3-wood not too bad but if I’m on the fairway I think I can give myself a good birdie putt and that’s the key.
“That’s why you see a lot of squares (bogeys) there but I’ll try and tidy that yup for tomorrow.”
Day said he expects conditions to remain difficult tomorrow and feels that will play into his favour though suggested much depends on the play of leader Thomas.
“It depends on how he plays,” he said of Thomas. “ I kind of picked 13 to 15-under to win the tournament.
“The course is getting firmer and faster on the fairways and the greens too to that will factor into how we attack the golf course but it shouldn’t yield too may low scores.
“I just need to be a little more patient tomorrow, hit a few more fairways and give myself the opportunities and if I can capitalise I should be around there at the end.”
McIlroy will be in the final group alongside Thomas tomorrow afternoon and also pointed to the driver as being key to his chances.
“I like to hit driver as much as possible and this course allows me to do that,” he said.
“Nine out of 14 fairways for me today is a good number and if I can do that again tomorrow hopefully I’ll have a chance.”
Expectations were high for eight-time winner of the tournament, Tiger Woods, prior to tee off but the 42-year-old endured a horror day on the course.
He struggled with all elements of his game on his way to a 3-over 73 which dropped him 11 shots off the pace and out of contention.
SIGNATURE HOLES - 3RD AT NAROOMA GC, NSW:
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